Alpha 21264: The Fastest RISC Chip for NT
The Alpha 21264 CPU: NT's Greatest RISC (1998)
Digital Equipment's Alpha 21264 is a 64-bit RISC processor that runs Windows NT and is already available, with clock speeds expected to exceed 700 MHz this year and reach 1 GHz by 2000. It executes up to six instructions per clock cycle, features out-of-order execution with 80 instructions in flight, and includes new motion video instructions for efficient MPEG-2 decoding. Despite the uncertain future of RISC and Digital's acquisition by Compaq, the Alpha 21264 could challenge Intel's upcoming IA-64 Merced for performance supremacy.
The 21264 juggles 80 instructions, more instructions than any other processor.
- fredoralive
The bit about how the AMD Athlon (K7) uses the same bus, and how they planned to make Slot A Alphas where the only adjustment an Althon motherboard would need is a different BIOS. Imagine what might have been, especially as Alpha Windows 2000 had a built in FX!32. Cheap Alpha systems with a good x86 compatibility story, it could've been a contender.
(Yeah, I know, several stars would've had to align for it to actually work).
- leoc
A video of an 1994 presentation put together for Hot Chips VI on the 21164: https://youtube.com/watch?v=OHupqMbLj1g
An April 1992 University Video Communications presentation on the Alpha architecture https://youtube.com/watch?v=klg1FtHADso and then from 38m 19s on the 21064 CPU https://youtube.com/watch?v=klg1FtHADso&t=2299s . From about 2m52s https://youtube.com/watch?v=klg1FtHADso&t=172s to 4m 43s Richard L. Sites gives the Alpha team’s predictions from 1992 for the next 12-25 of CPU development, which seem to have been fairly on the nail.
(Sites hasn’t been idle recently either! He’s responsible for the ultra-low-overhead KUTrace: https://news.ycombinator.com/item?id=40972099 )
- hinkley
Digital, HP, and IBM had the foresight to supply NCSA with Windows NT machines with their respective not-Intel chips in them to make sure that they had a web browser on their platforms. I got the honor of using the Alpha machine, and so it got the most QA by far. I recall spending an unnecessary amount of time not only staring at the heat sink but occasionally showing it to the new guy so they could confirm my astonishment.
Having the free hardware mostly worked, but there was a long time before all of the data alignment bugs got sorted out. It got to the point where my CS classes had progressed enough that I started looking for them myself. Literally the first development tasks I got paid to do was code reviewing for word alignment bugs on 64 bit code. It was a long goddamned time ago so it's pretty fuzzy but IIRC not all 3 processors had exactly the same restrictions for all data types. So if it worked on Alpha it usually worked on the other 2 but not 100%.
I didn't have to deal with 64 bit software at work again for another 10 years, at which point people looked at me like I was trying to be edgy when I just shrugged. No, really, I was looking at 64 bit code errors 10 years ago.
- jleyank
I seem to remember that Alpha’s were very fast for the time but their maximum optimization level waived IEEE floating point conformance. This, of course, drove us nuts trying to validate ports of numerically intensive code. Less interesting chips with lower optimization and limited market penetration.
Now, HP’s PA-RISC chips…. Those things were fast and easier to work with. Curiously, with SoftPC they could do windows faster than a 486 could. Slaughtered all sorts of mini-supers they did.
Would have been interesting if alpha survived to compete with SGI’s MIPS.
- MomsAVoxell
In those days, I was using SGI machines to build web sites for folks .. the Indy was very popular for this purpose. One day I was given a DEC Alpha machine to evaluate and see if it was a worthwhile addition to our inventory.
It came with NT, so there was some friction to just adding it to our services. These days were very frustrating - Microsoft was hell-bent on killing Unix, and later Linux also - and there was a lot of back and forth in our engineering team whether we wanted to invest in this hassle.
We didn't. I had that machine under my desk doing basically nothing for a year, before I sent it back.
If there had been a bit more insight into the nature of things, and if it had been running a Unix variant, we would have given it a better chance.
So then it was even more frustrating when SGI did a deal with the devil in later years, and tried to get its customers switch to NT, also. That killed SGI, in my opinion.
Looking back now, it's kind of incredible the resistance to Unix in those days, and how it was all going to be replaced with some "New Technology". Linux won. SGI didn't. And DEC was an early victim they should have learned from, in my opinion.